The Zeus board is still evolving. I’ve put a lot of thought into practical protection, but I’m not claiming it solves *every* problem. There’s always going to be some insane corner case where Zeus gets his thunderbolt through. I’m aiming for solid, affordable defense against the most common grid-born nasties — not lab-grade immunity or mythical indestructibility. Suggestions welcome, but keep it grounded.
It was on the input side. Both the transformer short-circuited and the capacitors and diodes in the little China box blew up. On the other hand, one of the spikes worked its way over to the raspberry pi as I mentioned in the article.
You probably know this, but for those who read this later, you have to be careful as a you can get a sharp voltage spike on the secondary side also if you get a sudden cutoff of voltage (at just the right time) on the primary. A lot of cheap power supplies don't handle that situation. I have lost a few micro-controllers thanks to cheap power supplies. Even had a fake "7805" over-voltage one of my custom boards and kill everything. I sure enjoy your posts, keep up the good work!
I have forgotten more than I remember about EE, but I do recall something about Lenz and how, when the magnetic field collapses in the primary, the secondary spike occurs because the field wants to keep on going. - and yeah, the whole counterfeit market and the shitty 7805 - they don’t clamp properly, and guess what they fail short, dumping input voltage straight into a 5V rail when zapped — especially if the input gets spiked. -- lets out the magic smoke
The Zeus board is still evolving. I’ve put a lot of thought into practical protection, but I’m not claiming it solves *every* problem. There’s always going to be some insane corner case where Zeus gets his thunderbolt through. I’m aiming for solid, affordable defense against the most common grid-born nasties — not lab-grade immunity or mythical indestructibility. Suggestions welcome, but keep it grounded.
Thanks to a hackaday contributor, I might update the MOV to something like a TMOV20RP275E THERMALLY PROTECTED VARISTOR
Note: I made a few minor revisions since my first release. Mostly a few drain resistors for the capacitors.
Was the failed trace/components on the input or output side of the power supply?
It was on the input side. Both the transformer short-circuited and the capacitors and diodes in the little China box blew up. On the other hand, one of the spikes worked its way over to the raspberry pi as I mentioned in the article.
This will not happen again
You probably know this, but for those who read this later, you have to be careful as a you can get a sharp voltage spike on the secondary side also if you get a sudden cutoff of voltage (at just the right time) on the primary. A lot of cheap power supplies don't handle that situation. I have lost a few micro-controllers thanks to cheap power supplies. Even had a fake "7805" over-voltage one of my custom boards and kill everything. I sure enjoy your posts, keep up the good work!
I have forgotten more than I remember about EE, but I do recall something about Lenz and how, when the magnetic field collapses in the primary, the secondary spike occurs because the field wants to keep on going. - and yeah, the whole counterfeit market and the shitty 7805 - they don’t clamp properly, and guess what they fail short, dumping input voltage straight into a 5V rail when zapped — especially if the input gets spiked. -- lets out the magic smoke